This invention relates to systems using terahertz radiation to detect particular types of articles.
Computerized tomography (CT) imaging has been employed for non-destructive examination of various types of articles, such as contraband, which may be hidden inside luggage. However, CT systems emit X-rays, which may pose a health risk to the operators of such systems, as well as passengers who may be standing near the system, and hence CT systems generally include some type of shield to protect the operators and passengers ionizing radiation. Moreover, although CT systems are capable of analyzing the density of an article, along with other characteristics of the shape and volume of the article, these systems do not have spectroscopic capabilities, and therefore cannot analyze the chemical compositions of the articles. Furthermore, X-rays are not sensitive to the optical traits that result from the article's refractive index and absorption coefficient. These properties, if measurable, can yield unique, high-contrast images and reveal much about the reflective, absorptive and scattering properties of material.
Thus, there is a need for a non-destructive imaging system that is also capable of providing optical and spectroscopic probing capabilities.